There is no <properties> section – use <properties-fragment> element instead or corresponding <document> attributes:

@add-fragment=false or @delete-fragment=false should set document/@lockstructure="true"

@broadcast-discussion=false is no longer supported

Move section/toc to document/toc (by default this is after the first <section> in Reference documents only) and programmatically remove toc/@maxLevel when converting from standard (non-master) PS XML to PSML.

Change <body id="[id]" type="[section type]"> to <fragment id="[id]"type="[fragment type]">.id can now be a simple incrementing integer with no constraints on the order it appears in the document.

Change <customBody> to <media-fragment> and changed attribute @contentType to @mediatype.

Remove section/@format and map fragment types to editors instead

If @edit="false" or @overwrite="false" it's easier to generate update documents externally if the structure is locked by setting document[@lockstructure="true"]